6533b850fe1ef96bd12a8637

RESEARCH PRODUCT

Some experimental issues of AFM tip blind estimation. The effect of noise and resolution

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The convolution of tip shape on sample topography can introduce significant inaccuracy in an AFM image, when the tip radius is comparable to the typical dimension of the sample features to be observed. The blind estimation method allows one to obtain information on the AFM tip through an unknown characterizer sample and thus to perform the deconvolution of the tip shape from an image. When applying the blind estimation method to determine the AFM tip shape, some apparently trivial issues relating to the experimental operating parameters must be taken into account. In this paper, the effects of the operating parameters, e.g., sampling intervals (resolution) and instrumental noise, have been taken into account for the practical use of blind estimation and the result is that instrumental noise tends to provide a smaller estimation of the tip size, while larger sampling intervals provide a larger value of it. This paper presents guidelines to those effects in AFM and appropriate experimental conditions for applying the blind estimation method to obtain more reliable data on tip radius and therefore on sample topography.